Beam-compass.



FRANK MACHAVA, OF GREENSBURG, PENNSYLVANIA.

BEAM-COMPASS.

Specification of Letters Patent.

Patented July 2, 191 2.

Application filed April 6, 1912. Serial No. 689,053.

To all whom it may concern:

Be it known that I, FRANK MACHAVA, a citizen of the United States of America, residing at Greensburg, in the county of l/Vestmoreland and State of Pennsylvania, have invented certain new and useful Improvements in Beam-Compasses, of which the following is a specification, reference being had therein to the accompanying drawing.

My invention relates to beam compasses, and the primary object of my invention is to provide a compass beam of strong and durable construction that can be advantageously used by a machinist for marking off circles and arcs upon a sheet of metal and such material in connection with which a large compass could not be conveniently used.

A. further object of this invention is to provide a beam compass that can be easily and quickly adjusted and set without any danger of the same slipping when in use.

WVith the above and other objects in view, the invention resides in the novel construction, combination and arrangement of parts to be hereinafter specifically described and then claimed.

Reference will now be had to the drawing wherein-- Figure 1 is a side elevation of the beam compass. Fig. 2 is a plan of the same. Fig. 3 is an enlarged longitudinal sectional view of the beam compass partly broken away, and Fig. 4 is a cross sectional view of the same.

To put my invention into practice I provide a laminated beam consisting of three plates, 1, 2, and 3, the plate 2 being arranged intermediate the plates 1 and 3. The plates are soldered or otherwise connected together and the plates 1 and 3 have longitudinal slots 4 and 5 respectively in communication with a large rectangular opening 6 in the plate 2, the slots 4 and 5 and the openings 6 extend from one end of the beam in proximity to the opposite end, and the plates 1, 2 and 3, at the inner end of the beam are provided with openings 7 and 8, the latter being formed in the plate 2 and of greater diameter than the former.

Mounted in the openings 7 and 8 is a bearing 9 having a collar 10 within the opening 8 that retains the hearing within the openings 7. Screwed into the bearing 9 is a pointed screw 11 that is locked within said hearing by a transverse pin 12. The screw 11 has a large handle 13 and by gripping the handle 13, the pointed screw can be used as a center point for swinging the beam.

Movably mounted in the opening 6 of the plate 2, and sliding between the plates 1 and 3 is a slide 14: that has a vertical sleeve 15 extending through the slots 4 and 5 and above the plate 1. Mounted upon the sleeve 15 is a transverse plate 16 having extensions 17 extending on to the plate 1. The ends of the extension 17 are provided with bosses 18 for set screws 19 employed for locking said extensions and the plate 16 relatively to the laminated beam. The ends of the plate 16 have depending portions 20 and secured to said depending portions by screws 21 or other fastening means are plates 22 that extend under the longitudinal edges of the plate 3 and coiiperate with the plates 1 and 3 in retaining the slide 141 in engagement with the beam.

Secured to the upper end of the sleeve 15 by set screws 23 and 2 1 is a socket member 25 that rests upon the plate 16. Arranged within the upper end of the socket member is the head 26 of a tubular adjusting member 27 having the upper end thereof provided with a knurled nut 28. The head 26 is retained within the socket member 25 by a washer 29 arranged within said member and retained therein by a set screw 30.

Adjustably held by the nut 28 is the upper threaded end 31 of a marker 32 that extends through the sleeve 15, said marker having a longitudinal groove 33 into which extends the end of a screw 24, said screw preventing the marker from rotating, but permitting of longitudinal movement of said marker relatively to said sleeve.

By adjusting the nut 28, the marker 32 can be raised and lowered, and by with drawing the pin 12 the bearing 9 can be raised and lowered upon the pointed screw 11, thereby permitting of the laminated beam being positioned a desired height above a piece of work to suit the convenience of an artisan. By adjusting the said screws 19, the marker can be shifted longitudinally of the beam and then set, whereby it can be swung to describe a circle or are.

The instrument in its entirety is made of light and durable metal, and the structural elements thereof are susceptible to such variations as fall within the scope of the appended claim.

What I claim is:

An instrument of the type described, comprising a laminated beam, a slide movably mounted in said beam, a sleeve carried thereby, a plate carried by said sleeve, a socket member arranged upon said sleeve, a tubular adjusting member having the lower end thereof rotatively held in said socket member, a marker extending through said adjusting member and said sleeve, a screw extending into said marker to prevent rotation thereof relatively to said sleeve, means carried by said plate and engaging said beam for holding said plate relatively to said beam, and means carried by the inner 15 FRANK MACHAVA.

Witnesses:

MAX H. SROLOVITZ, WANDA M. KULESZA.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

WaShington D. C. 

